1
|
Xu S, Wang F, Mai P, Peng Y, Shu X, Nie R, Zhang H. Mechanism Analysis of Vascular Calcification Based on Fluid Dynamics. Diagnostics (Basel) 2023; 13:2632. [PMID: 37627891 PMCID: PMC10453151 DOI: 10.3390/diagnostics13162632] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 08/05/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
Vascular calcification is the abnormal deposition of calcium phosphate complexes in blood vessels, which is regarded as the pathological basis of multiple cardiovascular diseases. The flowing blood exerts a frictional force called shear stress on the vascular wall. Blood vessels have different hydrodynamic properties due to discrepancies in geometric and mechanical properties. The disturbance of the blood flow in the bending area and the branch point of the arterial tree produces a shear stress lower than the physiological magnitude of the laminar shear stress, which can induce the occurrence of vascular calcification. Endothelial cells sense the fluid dynamics of blood and transmit electrical and chemical signals to the full-thickness of blood vessels. Through crosstalk with endothelial cells, smooth muscle cells trigger osteogenic transformation, involved in mediating vascular intima and media calcification. In addition, based on the detection of fluid dynamics parameters, emerging imaging technologies such as 4D Flow MRI and computational fluid dynamics have greatly improved the early diagnosis ability of cardiovascular diseases, showing extremely high clinical application prospects.
Collapse
Affiliation(s)
- Shuwan Xu
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Feng Wang
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Peibiao Mai
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| | - Yanren Peng
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Xiaorong Shu
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Ruqiong Nie
- Department of Cardiology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou 510120, China; (Y.P.); (X.S.)
| | - Huanji Zhang
- Department of Cardiology, The Eighth Affiliated Hospital of Sun Yat-Sen University, Shenzhen 518033, China; (S.X.); (F.W.); (P.M.)
| |
Collapse
|
2
|
Yang CY, Chang PY, Wu BS, Tarng DC, Lee OKS. Mechanical and chemical cues synergistically promote human venous smooth muscle cell osteogenesis through integrin β1-ERK1/2 signaling: A cell model of hemodialysis fistula calcification. FASEB J 2021; 35:e22042. [PMID: 34758125 DOI: 10.1096/fj.202101064rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 10/25/2021] [Accepted: 10/29/2021] [Indexed: 11/11/2022]
Abstract
Arteriovenous fistula (AVF) is the vascular access of choice for renal replacement therapy. However, AVF is susceptible to calcification with a high prevalence of 40%-65% in chronic hemodialysis patients. Repeated needle puncture for hemodialysis cannulation results in intimal denudation of AVF. We hypothesized that exposure to blood shear stress in the medial layer promotes venous smooth muscle cell (SMC) osteogenesis. While previous studies of shear stress focused on arterial-type SMCs, SMCs isolated from the vein had not been investigated. This study established a venous cell model of AVF using the fluid shear device, combined with a high phosphate medium to mimic the uremic milieu. Osteogenic gene expression of venous SMCs upon mechanical and chemical cues was analyzed in addition to the activated cell signaling pathways. Our findings indicated that upon shear stress and high phosphate environment, mechanical stimulation (shear stress) had an additive effect in up-regulation of an early osteogenic marker, Runx2. We further identified that the integrin β1-ERK1/2 signaling pathway was responsible for the molecular basis of venous SMC osteogenesis upon shear stress exposure. Mitochondrial biogenesis also took part in the early stage of this venopathy pathogenesis, evident by the up-regulated mitochondrial transcription factor A and mitochondrial DNA polymerase γ in venous SMCs. In conclusion, synergistic effects of fluid shear stress and high phosphate induce venous SMC osteogenesis via the ERK1/2 pathway through activating the mechanosensing integrin β1 signaling. The present study identified a promising druggable target for reducing AVF calcification, which deserves further in vivo investigations.
Collapse
Affiliation(s)
- Chih-Yu Yang
- Institute of Clinical Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Center for Intelligent Drug Systems and Smart Bio-Devices (IDS2B), Ministry of Education, Taipei, Taiwan.,Stem Cell Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Pu-Yuan Chang
- Institute of Clinical Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Bo-Sheng Wu
- Institute of Clinical Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Der-Cherng Tarng
- Institute of Clinical Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Center for Intelligent Drug Systems and Smart Bio-Devices (IDS2B), Ministry of Education, Taipei, Taiwan
| | - Oscar Kuang-Sheng Lee
- Institute of Clinical Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Faculty of Medicine, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Stem Cell Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Department of Orthopedics, China Medical University Hospital, Taichung, Taiwan
| |
Collapse
|
3
|
Kim K, Anderson EM, Martin AJ, Hu Q, Cort TA, Harland KC, O'Malley KA, Lu G, Berceli SA, Ryan TE, Scali ST. Development of a murine iliac arteriovenous fistula model for examination of hemodialysis access-related limb pathophysiology. JVS Vasc Sci 2021; 2:247-259. [PMID: 34816137 PMCID: PMC8591416 DOI: 10.1016/j.jvssci.2021.09.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/27/2021] [Indexed: 11/07/2022] Open
Abstract
OBJECTIVE Hemodialysis access-related hand dysfunction is a common clinical feature of patients with chronic kidney disease (CKD) after arteriovenous fistula (AVF) placement. The heterogeneity in symptoms and the lack of a predictive association with changes in hemodynamic alterations precipitated by the AVF suggest that other factors are involved in the mechanisms responsible for causing hand and limb dysfunction postoperatively. To the best of our knowledge, no suitable animal models have provided a platform for performing preclinical experiments designed to elucidate the biologic drivers of access-related hand dysfunction. Therefore, our objective was to develop a novel murine AVF model that could be used to study dialysis access-related limb dysfunction. METHODS Male 8-week-old C57BL/6J mice (n = 15/group) were exposed to either an adenine-supplemented diet to induce CKD or casein-based chow (control). Four weeks after the diet intervention, the mice were randomly assigned to receive an iliac AVF (n = 10/group) or sham surgery (n = 5/group) on the left hindlimb. The mice were sacrificed 2 weeks after surgery, and AVF specimens and hindlimb skeletal muscles were collected for further analysis. RESULTS Before AVF or sham surgery, the glomerular filtration rates were significantly reduced and the blood urea nitrogen levels were significantly elevated in the CKD groups compared with the controls (P < .05). AVF surgery was associated with an ∼80% patency rate among the survivors (four control and three CKD mice died postoperatively). Patency was verified by changes in hemodynamics using Doppler ultrasound imaging and altered histologic morphology. Compared with sham surgery, AVF surgery reduced ipsilateral hindlimb perfusion to the tibialis anterior muscle (20%-40%) and paw (40%-50%), which remained stable until euthanasia. Analysis of gastrocnemius muscle mitochondrial respiratory function uncovered a significant decrease (40%-50%) in mitochondrial function in the AVF mice. No changes were found in the muscle mass, myofiber cross-sectional area, or centrally nucleated fiber proportion in the extensor digitorum longus and soleus muscles between the sham and AVF mice. CONCLUSIONS The results from the present study have demonstrated that iliac AVF formation is a practical animal model that facilitates examination of hemodialysis access-related limb dysfunction. AVF surgery produced the expected hemodynamic changes, and evaluation of the limb muscle revealed a substantial mitochondrial impairment that was present without changes in muscle size.
Collapse
Affiliation(s)
- Kyoungrae Kim
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Fla
| | - Erik M. Anderson
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Andrew J. Martin
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Qiongyao Hu
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Tomas A. Cort
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Fla
| | - Kenneth C. Harland
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Kerri A. O'Malley
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Guanyi Lu
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
| | - Scott A. Berceli
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Fla
- Center for Exercise Science, University of Florida, Gainesville, Fla
| | - Salvatore T. Scali
- Division of Vascular Surgery and Endovascular Therapy, University of Florida, Gainesville, Fla
- Malcolm Randall Veteran Affairs Medical Center, Gainesville, Fla
| |
Collapse
|
4
|
Hashimoto T, Yamamoto K, Foster T, Bai H, Shigematsu K, Dardik A. Intraluminal Drug Delivery to the Mouse Arteriovenous Fistula Endothelium. J Vis Exp 2016:e53905. [PMID: 26967580 DOI: 10.3791/53905] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The simple murine AVF model was combined with intraluminal administration of drug solution to the venous endothelium at the same time as fistula creation. Technical aspects of this model are discussed. Under general anesthesia, an abdominal incision is made and the aorta and inferior vena cava (IVC) are exposed. The infra-renal aorta and IVC are dissected for clamping. After proximal and distal clamping, the puncture site is exposed and a 25 G needle is used to puncture both walls of the aorta and into the IVC. Immediately after the puncture, a reporter gene-expressing viral vector was infused in the IVC via the same needle, followed by 15 min of incubation. The intraluminal administration method enabled more robust viral gene delivery to the venous endothelium compared to administration by the external route. This novel method of delivery will facilitate studies that explore the role of the endothelium in AVF maturation and enable intraluminal drug delivery at the time of surgical operation.
Collapse
Affiliation(s)
- Takuya Hashimoto
- Department of Surgery and the Vascular Biology and Therapeutics Program, Yale University; Department of Vascular Surgery, University of Tokyo; Department of Vascular Surgery, VA Connecticut Healthcare Systems
| | - Kota Yamamoto
- Department of Surgery and the Vascular Biology and Therapeutics Program, Yale University; Department of Vascular Surgery, University of Tokyo; Department of Vascular Surgery, VA Connecticut Healthcare Systems
| | - Trenton Foster
- Department of Surgery and the Vascular Biology and Therapeutics Program, Yale University
| | - Hualong Bai
- Department of Surgery and the Vascular Biology and Therapeutics Program, Yale University
| | - Kunihiro Shigematsu
- Department of Vascular Surgery, International University of Health and Welfare Mita Hospital
| | - Alan Dardik
- Department of Surgery and the Vascular Biology and Therapeutics Program, Yale University; Department of Vascular Surgery, VA Connecticut Healthcare Systems;
| |
Collapse
|
5
|
Zheng C, Zhou Y, Huang C, Zhang Z, Liu YI, Xu Y. Establishment of a rat autogenous arteriovenous fistula model following 5/6 nephrectomy. Exp Ther Med 2015; 10:219-224. [PMID: 26170938 DOI: 10.3892/etm.2015.2451] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 03/05/2015] [Indexed: 12/30/2022] Open
Abstract
The aim of this study was to establish a stable rat model of autogenous arteriovenous fistula (AVF) with chronic renal function insufficiency. Forty Sprague-Dawley rats were randomly divided into an experimental group (n=20) and sham surgery group (n=20) and a 5/6 nephrectomy model was established in the rats. One week later, in the experimental group, the ipsilateral caroid artery was inserted into the external jugular vein by a cuff technique to establish a carotid arteriovenous fistula; in the sham group, the external jugular vein and carotid artery were dissociated. At 7 and 28 days following the establishment of the AVF, the renal functions of the two groups were measured. Hematoxylin and eosin staining and double collagen and elastin staining were conducted to evaluate the area of intimal hyperplasia in the external jugular vein, and the expression of α-smooth muscle actin in the vein was investigated by immunohistochemistry. The creatinine and urea nitrogen levels in the experimental group at each time-point were significantly higher than those in the sham surgery group (P<0.05). The intimal hyperplasia of the external jugular vein of the experimental group was increased significantly compared with that in the sham group at each time-point (P<0.05). The model, which is easy to establish and simple to master, provides a new and feasible experimental method for the study of intimal hyperplasia associated with autogenous AVF in chronic renal insufficiency, and is worthy of wider use.
Collapse
Affiliation(s)
- Chenfei Zheng
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Ying Zhou
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Chaoxing Huang
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Zhouchang Zhang
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Y I Liu
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| | - Yulan Xu
- Department of Nephrology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China
| |
Collapse
|
6
|
Yamamoto K, Protack CD, Tsuneki M, Hall MR, Wong DJ, Lu DY, Assi R, Williams WT, Sadaghianloo N, Bai H, Miyata T, Madri JA, Dardik A. The mouse aortocaval fistula recapitulates human arteriovenous fistula maturation. Am J Physiol Heart Circ Physiol 2013; 305:H1718-25. [PMID: 24097429 DOI: 10.1152/ajpheart.00590.2013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Several models of arteriovenous fistula (AVF) have excellent patency and help in understanding the mechanisms of venous adaptation to the arterial environment. However, these models fail to exhibit either maturation failure or fail to develop stenoses, both of which are critical modes of AVF failure in human patients. We used high-resolution Doppler ultrasound to serially follow mice with AVFs created by direct 25-gauge needle puncture. By day 21, 75% of AVFs dilate, thicken, and increase flow, i.e., mature, and 25% fail due to immediate thrombosis or maturation failure. Mature AVF thicken due to increased amounts of smooth muscle cells. By day 42, 67% of mature AVFs remain patent, but 33% of AVFs fail due to perianastomotic thickening. These results show that the mouse aortocaval model has an easily detectable maturation phase in the first 21 days followed by a potential failure phase in the subsequent 21 days. This model is the first animal model of AVF to show a course that recapitulates aspects of human AVF maturation.
Collapse
Affiliation(s)
- Kota Yamamoto
- Veterans Affairs Connecticut Healthcare Systems, West Haven, Connecticut
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Yamamoto K, Li X, Shu C, Miyata T, Dardik A. Technical aspects of the mouse aortocaval fistula. J Vis Exp 2013:e50449. [PMID: 23892387 DOI: 10.3791/50449] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.
Collapse
Affiliation(s)
- Kota Yamamoto
- Department of Surgery and the Interdepartmental Program in Vascular Biology and Therapeutics, Yale University, USA
| | | | | | | | | |
Collapse
|
8
|
Manning E, Skartsis N, Orta AM, Velazquez OC, Liu ZJ, Asif A, Salman LH, Vazquez-Padron RI. A new arteriovenous fistula model to study the development of neointimal hyperplasia. J Vasc Res 2012; 49:123-31. [PMID: 22249138 DOI: 10.1159/000332327] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 08/19/2011] [Indexed: 11/19/2022] Open
Abstract
This study describes an alternative arteriovenous fistula (AVF) model in the rat in which the animals develop significant neointimal hyperplasia (NIH) not only at the distal anastomotic site, but also throughout the fistula body. This aortocaval fistula was established by anastomosing the distal end of the renal vein to the abdominal aorta after unilateral nephrectomy. The increased hemodynamic stress resulting from exposing the renal vein to the arterial circulation induced venous NIH as early as 7 days after surgery. This experimental AVF was characterized by the early lack of endothelium, the accumulation of proliferating vascular smooth muscle cells and the neovascularization of the fistula adventitia. In summary, we have described an informative animal model to study the pathobiology of NIH in native AVF.
Collapse
Affiliation(s)
- Eddie Manning
- DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Fla. 33136, USA
| | | | | | | | | | | | | | | |
Collapse
|
9
|
Angouras DC, Dosios TJ, Dimitriou CA, Chamogeorgakis TP, Rokkas CK, Manos TA, Sokolis DP. Surgical Thoracic Sympathectomy Induces Structural and Biomechanical Remodeling of the Thoracic Aorta in a Porcine Model. J Surg Res 2012; 172:68-76. [DOI: 10.1016/j.jss.2010.07.039] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 06/20/2010] [Accepted: 07/16/2010] [Indexed: 10/19/2022]
|
10
|
Bond AR, Iftikhar S, Bharath AA, Weinberg PD. Morphological evidence for a change in the pattern of aortic wall shear stress with age. Arterioscler Thromb Vasc Biol 2011; 31:543-50. [PMID: 21205986 DOI: 10.1161/atvbaha.110.219683] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The distribution of atherosclerosis around branch sites changes with age in human and rabbit aortas. We tested whether that reflects a change in the pattern of wall shear stress by examining shear-dependent morphological features of endothelial cells. METHODS AND RESULTS Endothelial cells and their nuclei align and elongate with applied shear. These parameters were examined in the descending thoracic aorta of immature and mature rabbits. The use of Häutchen preparations, fluorescent stains, and automated image analysis allowed nuclear morphology to be mapped reliably at high resolution over large areas. Cells and their nuclei were most elongated downstream of branch ostia in immature aortas but upstream of them in mature aortas. Elongation was generally greater in mature animals, and nuclei aligned toward the ostia more in these animals, consistent with a greater flow into the branch. Morphology away from branches was indicative of helical flow in the aorta, with greatest shear on the dorsal wall, at both ages. CONCLUSIONS The data are consistent with age-related changes in the pattern of shear around aortic branches. Maps of nuclear elongation closely resembled maps of lesion frequency. The association was positive, implying that lesions occur at sites of high shear stress at both ages.
Collapse
Affiliation(s)
- Andrew R Bond
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | | | | | | |
Collapse
|
11
|
Cardiovascular remodeling during arteriovenous fistula maturation in a rodent uremia model. J Vasc Access 2010; 12:215-23. [PMID: 21104672 DOI: 10.5301/jva.2010.6066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2010] [Indexed: 11/20/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate cardiovascular remodeling after arteriovenous fistula (AVF) surgery and to characterize the effect of chronic kidney disease (CKD) in a rodent femoral AVF model. METHODS Sixteen rats (8 healthy; 8 CKD) underwent femoral AVF surgery; 4 animals served as controls. AVF and cardiac morphology as well as function were assessed during the fistula maturation process (until day 84 after surgery) using magnetic resonance imaging and histopathological analyses. RESULTS Histopathological analysis revealed that a glomerular and interstitial nephropathy caused CKD. In healthy and CKD animals, AVF surgery resulted in progressive downstream vein dilation and a subsequent cardiac adaptation. This vein dilation during maturation was less in CKD rats during the early postoperative course (day 21: p=0.0475) and similar thereafter until day 84. The dilation was accompanied by an aggravation of neointimal hyperplasia (NIH) and calcification in AVFs of CKD rats. The chronic volume overload resulted in both groups in a significantly increased end-diastolic volume (healthy rats: p=0.0087; CKD rats: p=0.0333). Simultaneously, cardiac output increased 195% in healthy and 244% in uremic rats, which was caused by both a significantly increased stroke volume and heart rate. The left ventricular mass rose in AVF animals and was increased at the end of the study period, indicating a distinct cardiac hypertrophy. CONCLUSION Our rat model showed typical cardiovascular features of the AVF maturation process, which strongly resemble clinical findings in patients. Uremia caused inferior dilation in the early phase after surgery and an exacerbation of NIH. This model should help to identify the cellular and molecular mechanisms that contribute to AVF failure.
Collapse
|
12
|
Zhao X, Pratt R, Wansapura J. Quantification of aortic compliance in mice using radial phase contrast MRI. J Magn Reson Imaging 2009; 30:286-91. [PMID: 19629988 DOI: 10.1002/jmri.21846] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To investigate the feasibility of radial phase contrast MR imaging to measure in vivo pulse wave velocity (PWV) and wall shear stress (WSS) in small animals on a 7 Tesla scanner. MATERIALS AND METHODS The aortic compliance of 9-month-old ApoE deficient (ApoE-KO) mice (n = 10) on a normal diet was studied in comparison to that of wild-type (WT) mice (n = 10). An undersampled, asymmetric echo radial phase contrast MR technique was developed to measure through plane blood flow velocity at axial slices along the descending aorta. The PWV and the time averaged WSS was calculated from the spatiotemporal flow data. The reproducibility of PWV and WSS was evaluated by taking multiple measures on a separate cohort of WT (n = 4) mice. RESULTS The mean percentage standard deviation among repeated measures was 10.1% for PWV and 24.8% for WSS. The PWV of ApoE-KO mice (5.84 +/- 2.15 m/s) was significantly higher (p = 0.02) than that of WT (3.55 +/- 0.97 m/s), whereas WSS was lower in ApoE-KO mice (1.44 +/- 0.31Pa) compared with WT (1.55 +/- 0.36Pa). CONCLUSION This study demonstrates that in vivo PWV derived from radial phase contrast MR imaging can be potentially used as a surrogate marker for impaired vascular function in mice.
Collapse
Affiliation(s)
- Xuandong Zhao
- Cincinnati Children's Hospital Medical Center, Department of Radiology/Imaging Research Center, Cincinnati, Ohio 45229-3039, USA
| | | | | |
Collapse
|
13
|
Dorsett-Martin WA, Hester RL. Sex hormones and aortic wall remodeling in an arteriovenous fistula. ACTA ACUST UNITED AC 2007; 4:157-69. [PMID: 17707849 DOI: 10.1016/s1550-8579(07)80029-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2007] [Indexed: 11/27/2022]
Abstract
BACKGROUND An arteriovenous fistula (AVF) creates high blood flow through the artery and fistula. With this high flow, there is flow-induced remodeling and an increase in diameter, but no intimal hyperplasia. Estrogen has been shown to modify vascular remodeling, decreasing intimal hyperplasia after endothelial injury. OBJECTIVE These experiments tested the hypothesis that estrogen administration would decrease wall thickness in an AVF model. Because estrogen may decrease wall thickness, we also tested the hypothesis that testosterone would increase wall thickness. METHODS A fistula was created between the abdominal aorta and the inferior vena cava in Sprague-Dawley rats to generate high blood flow conditions in the aorta. Four groups of female animals were examined: sham, control with AVF ovariectomized (OVX) with AVF and OVX plus testosterone with AVF Four groups of male animals were also examined: sham, control with AVF castrated with AVF and castrated plus estrogen with AVF Five weeks after creation of the AVF, the aortas were collected and fixed; wall thickness was measured both proximal and distal to the AVF. RESULTS Ovariectomy resulted in a significant decrease in estrogen levels (P < 0.01). Testosterone administration tended to increase testosterone levels in the OVX females, but values did not approach levels observed in the control males. No difference was noted in the proximal wall thickness between the control and the OVX animals. The OVX females receiving testosterone exhibited a significant increase in both proximal and distal wall thickness compared with control females (P < 0.001). In the male animals, there was no significant change in aortic wall thickness in the castrated rats compared with the controls. Estrogen administration in the castrated males resulted in a significant decrease in wall thickness in the proximal and distal aorta (P < 0.05). CONCLUSION These studies suggest that, in a model of vascular remodeling, estrogen administration decreases wall thickness, and testosterone administration increases wall thickness.
Collapse
Affiliation(s)
- Wanda A Dorsett-Martin
- Department of Surgery, University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, USA.
| | | |
Collapse
|
14
|
Greve JM, Les AS, Tang BT, Draney Blomme MT, Wilson NM, Dalman RL, Pelc NJ, Taylor CA. Allometric scaling of wall shear stress from mice to humans: quantification using cine phase-contrast MRI and computational fluid dynamics. Am J Physiol Heart Circ Physiol 2006; 291:H1700-8. [PMID: 16714362 DOI: 10.1152/ajpheart.00274.2006] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Allometric scaling laws relate structure or function between species of vastly different sizes. They have rarely been derived for hemodynamic parameters known to affect the cardiovascular system, e.g., wall shear stress (WSS). This work describes noninvasive methods to quantify and determine a scaling law for WSS. Geometry and blood flow velocities in the infrarenal aorta of mice and rats under isoflurane anesthesia were quantified using two-dimensional magnetic resonance angiography and phase-contrast magnetic resonance imaging at 4.7 tesla. Three-dimensional models constructed from anatomic data were discretized and used for computational fluid dynamic simulations using phase-contrast velocity imaging data as inlet boundary conditions. WSS was calculated along the infrarenal aorta and compared between species to formulate an allometric equation for WSS. Mean WSS along the infrarenal aorta was significantly greater in mice and rats compared with humans (87.6, 70.5, and 4.8 dyn/cm2, P < 0.01), and a scaling exponent of −0.38 ( R2 = 0.92) was determined. Manipulation of the murine genome has made small animal models standard surrogates for better understanding the healthy and diseased human cardiovascular system. It has therefore become increasingly important to understand how results scale from mouse to human. This noninvasive methodology provides the opportunity to serially quantify changes in WSS during disease progression and/or therapeutic intervention.
Collapse
Affiliation(s)
- Joan M Greve
- Clark Center, E350, 318 Campus Dr., Stanford, CA 94305-5431, USA
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Karram T, Hoffman A, Bishara B, Brodsky S, Golomb E, Winaver J, Abassi Z. Induction of cardiac hypertrophy by a controlled reproducible sutureless aortocaval shunt in the mouse. J INVEST SURG 2006; 18:325-34. [PMID: 16319054 DOI: 10.1080/08941930500328839] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Much of the understanding about the pathophysiological responses to chronic cardiac overload has been gained by the use of rat and dog models of aortocaval fistula (ACF). The use of a similar model in genetically manipulated mice may further elucidate the molecular mechanisms in these responses. The only reports about ACF in mice to date have applied a needle puncture to create the ACF, which may result in an uncontrolled and irreproducible size of the shunt, and require several weeks to induce the characteristic cardiac changes. In order to obtain a more consistent approach to characterize this mode of cardiac hyperfunction, we present a surgical murine model of ACF that results in rapid progression of the typical systemic and cardiac changes. A sutureless side-to-side infrarenal surgical anastomosis of 0.6-0.8 mm in diameter was created between the abdominal aorta and inferior vena cava in ICR (Institute of Cancer Research) mice. Six to 7 days later, significant cardiac hypertrophy developed. The heart/body weight ratio increased from 0.45 +/- 0.02% in control mice to 0.77 +/- 0.03% in mice with ACF (p < .003). The dry heart weight ratio increased from 0.099 +/- 0.0033% to 0.13 +/- 0.008% (p < .006). The ACF dramatically induced the atrial and ventricular expression of atrial natriuretic factor mRNA, and increased the total cardiac content of endothelin-1 (162.5 +/- 50.6 vs. 83.9 +/- 9.0 pg). Mean arterial pressure in anesthetized mice with ACF decreased from 69.8 +/- 4.9 to 54.8 +/- 5.5 mm Hg (p < .025). Urinary sodium excretion returned to preoperative levels several days following surgery. These results demonstrate that cardiac hypertrophy could be rapidly and reproducibly achieved in mice by the placement of a surgical ACF. This model, when applied in genetically manipulated mice, may be a valuable tool for functional genomic studies about the pathogenesis of cardiac hypertrophy and heart failure.
Collapse
Affiliation(s)
- Tony Karram
- Department of Vascular Surgery and Transplantation Unit, Rambam Medical Center, Haifa, Israel
| | | | | | | | | | | | | |
Collapse
|
16
|
Affiliation(s)
- Anupam Agarwal
- Department of Medicine, Division of Nephrology, Hypertension and Transplantation, University of Florida College of Medicine, Gainesville, Florida, USA.
| | | |
Collapse
|